Combustion chambers for gas turbine power plants



July 12, 1960 v. H. PAVLECKA COMBUSTION CHAMBERS FOR GAS TURBINE POWERPLANTS 4 Sheets-Sheet 1 Original Filed March 19, 1951 ew v. kvbQ 4.3K

INVEN TOR. Wee/Mae 1!- PA a [ac/7 July 12, 1960 v. H. PAVLECKACOMBUSTION CHAMBERS FOR GAS TURBINE POWER PLANTS 4 Sheets-Sheet 2Original Filed March 19, 1951 July 12, 1960 v. H. PAVLECKA 2,944,397

COMBUSTION CHAMBERS FOR GAS TURBINE POWER PLANTS Original Filed March19, 1951 4 Sheets-Sheet 3 IN V EN TOR.

July 12, 1960 v. H. PAVLECKA 2,944,397

COMBUSTION CHAMBERS FOR GAS TURBINE POWER PLANTS Original Filed March19, 1951 4 Sheets-Sheet 4 vaer/c/A/a 5e57 Awe I (Ae/Mmev Ame 12 56.6: we400 (004 we fissca/voaeu AA?) 4 I 1 I I I 1 I I i I i 40;

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BY (44 7%&

American Machine & Foundry Company, a corporation of New Jersey Originalapplications Mar. 23, 1951, Ser. No. 217,347, and Mar. 19, 1951, Ser.No. 216,305, now Patent Nos. 2,804,747, dated Sept. 3, 1957, and2,809,493,dated Oct. 15, 1957. Divided and this application Aug-27,1956, Ser. No. 606,451

" Claims. (Cl. 60-3936) This invention relates to combustion chambersfor power plants where compressed air and fuel are mixed andburned forproducing heated gases which are then 'used as a. source of kinetic andpotential energy. Combustion chambers of the above type find theirwidest apatentflice Patented July 12, 1960 being uniformly distributedaround the outer periphery of the toroid inp'ne type of chamber, andaround the inner periphery of the toroid in another-type of chamber.

The novel features which are believed to be characteradvantages thereof,will'be better understood from the plication at 'this time in gasturbine power plants where a,

a dynamic compressor supplies compressed air into the chamber; a fuelpump also supplies fuel into the chamber, where it is, burned, andheated gases are expanded through a turbine which furnishes a motivepower for operating the compressor. The useful power may be a shaftpower or a thrust. In the latter case, the gas turbines of the abovetype are generally known as jet engines.

This application for patent is a divisional application of the parentapplication Serial No. 217,347, filed March 23, 1951, titled Gas TurbinePower Plant With a Supersonic Centripetal Flow Compressor andCentrifugal Flow I combustion chamber having a plurality of wedge-shapedinput ports for receiving compressed air and a corresponding pluralityof output ports for discharging heated gases. 5

It is also an object of this invention to provide a combustion chambershaped as a toroid, and having a plurality of exit andentry ports, saidchamber being constructed to have a staionary flame front located' atthe center of the toroid and stationary vortex flame'mass,

thusv insuring the geometric stability of the combustion locus andeliminating, the blow-outs which occur in combustion chambers in whichstabilization of the flame front is obtained by means of baflle plateswithin the chambers.

It is an additional object of this invention to provide 'a toroidallyshaped combustion chamber which can be made to rotate with acompressor-turbine combination, and which can be made as a stationarycombustion chamber positioned betweena compressor and a turbine.

Yet an additional object of this invention is to provide a toroidallyshaped combustion chamber having an inner toroid for burning fuel and anouter toroid, surrounding the inner toroid, the outer toroid receivingcompressed air from thecompressor and discharging it into hot gasesleaving the inner toroid, the compressed air, flowing between the twotoroids, acting as a cooling medium for the wall of the inner toroid.

It is also an object of this invention to provide a toroidally-shapedcombustion chamber havinginput and 5 output ports mutually interleavingeach other, the input ports having fuel nozzles, said input ports andnozzles following description considered in connection-with theaccompanying drawings in which several embodiments are illustrated byway of examples. It is to be expressly understood, however, that thedrawings are for the purpose of illustration and description only, andare not intended as a definition of the limits of the invention.

In the drawings,

Figure 1 is a vertical sectional view of the upper half of the toroidalcombustion chamber mounted between the second compressor stage and thefirst turbine stage and rotatable with these stages as a singlemechanical unit; the sectional view is taken along a plane passingthrough the horizontal axis of rotation of the power plant.

Figure 2 is a portion of the vertical transverse section of thecombustion chamber illustrated in Fig 1, the vertical section beingtaken along'line 2-2, illustrated in Fig.1. i Y

Figure 3 is a perspective view of the combustion chamber illustrated inFigs. 1 and 2'with a portion of the.

- periphery.

Figure 5 is a transverse vertical section of the combustion chamberillustrated in Figure 4, the sectionbeing taken along line 5'-5 shown inFig. 4.

Figure 6 is an inner viewvofthe combustion chamber illustrated'inFigures 4 and 5, the view being taken along line 66 illustrated inFigure 5.

Before proceeding with the detailed description, general principles ofoperation "applicable to the'toroidal combustion chambers will be givenfirst'and these. principles will be compared with those used inconnection with the combustion chambers now in use and thus known to theprior art. a '1 The disclosed combustion heat generators use a novel'process of combustion, which is particularly applicable to aircraft jetengines because of the stationary nature of the flame front. Combustionheat generators known to the prior art function on the basis of burningfuel on aflame front the stability of which is a function of thevelocity of the air entering the combustion zone of the chamber. Sincethe maximum flame propagation velocity with liquid hydro-carbon fuels'is of the order of 15 feet per second, the velocity 'of the air enteringthe combustion chamber cannot exceed this velocity. If the air velocitydoes exceed this limit of =15 feet per second, the flame front willbegin to recede atthe velocityin excess of 15 feet per second. Since thecombustion chambers known and used by the prior art are all of thestraight-through flow type, whether they use canister or annulusconfigurations, the stability and the actual position of the flame frontis a direct function 'ficient combustion ceases because of poor ignitionand shortened path available for completing combustion of fuel. When theair velocity becomes still higher, the flame front is blown out of thechamber altogether, and the power plant ceases to function altogether.Restarting is diflicult because of low ambient pressure, and low densityof air at high altitudes which create high air velocity in thecombustion chambers. Therefore,

, the operating ceiling of aircraft is limited by the flame frontvelocity in the straight-through flow in the com bustion chambers.

When flame-front stabilizing baflles are used withinthe'straight-through flow chambers, the straight-through flow combustionchambers inherently offer high resistance to air flow. The loss ofpressure may be of the order of 8% of the total pressure at the entry tothe combustion chamber. Such pressure loss cannot be recovered bysubsequent diffusion and heating of air in the cornbustion-chaniber.Since the compression ratio in the known turbo-jet power plants is notespecially high, such loss of pressure is especially disappointing sincethe thermodynamic and propulsive efliciencies of jet power plants arethe functions of the compression ratios.

The toroidal vortex heat generator disclosed in Figures 1 through 6function on the principle of vortex rotation of a flame mass, theposition of the center of the vortex with respect to the longitudinalaxis of the power plant being fixed, or stationary, irrespective of theair velocity through the toroidal chamber. Any increase or decrease inair velocity can have no other effect on the flame mass but only toincrease or decrease its angular velocity, i.e., the rotation of the airmass around the center of the vortex, but the center of vortex willremain firmly fixed within the chamber. Therefore, blowing the flamefront out of the toroidal vortex chamber is a physical impossibility.

In describing the functioning of the straight-through flow chambers, ithas been stated that the efliciency of combustion in such chambers isaffected by the air velocity through the chamber. While this is alsotrue of the toroidal vortex chamber in theoretical sense, sinceindefinite increase in the angular velocity of the vortex eventually mayreach such limits as to produce incomplete combustion, in practicalsense this is not so because the operating limits for sustainingeflicient combustion with the toroidal chamber are much wider than isthe case with the known chambers. This is so because the hottest regionin the toroidal chamber is at the center of the vortex, the locus ofthis center remaining stationary irrespective of the air velocity;therefore, this hottest center is a constant source of heat forsustaining or maintaining efficient combustion. The combustionefficiency will begin to decrease when the hottest region will begin todiminish in its diameter because of the excessive velocity of gases. Toprevent such contingency, the diameter of the chamber may be increasedin advance to include the range of such high air velocities, and what isimportant, such increase in diameter is within the practical limits ofthe toroidal chamber. A corresponding increase in length of thestraightthrough flow chambers is not as practicable because theresulting shift in the flame front is bound to produce inefficientcombustion.

Before proceeding with the description of the physical configuration ofthe chambers, a brief description of the functional cycle will be givenfirst, which will facilitate the understanding of its actual mechanicalconfiguration. The combustion chamber has the shape of a toroid. Coldair enters the toroid around its inner periphery in one embodiment(Figures 1-3) and along the outer periphery in another version, (Figures46). Upon entering the toroid, the air produces a toroidal vortex withinthe chamber, the center of the vortex being somewhat displaced outwardlyfrom the center of the toroid if there is an axial rotation ofthetoroid, The vortex is continuous around theperiphery of the chamber,Theangular velocity of the vortex is not uniform, it is higher at theinner periphery of the toroid, and lower at the outer periphery becauseof the variation in the radial distance of the air particles from thecentral axis of the entire toroid, i.e., the longitudinal axis of thejet plant around which the toroid revolves in Figures 1-3. Fuel isbrought into the chamber by atomizing jets which spray the fuel into thecenter of the toroid whereit' is burned under conditions of randomturbulence within the central portion of the vortex. Therefore, thecombustion phnomena'can be imagined to contain a centrally located hottoroid surrounded by a cooler toroid, cold air entering the toroid,following at first its outerwalls. High angular velocity exists'at thecenter of the vortex and it diminishes in radial direction from thecenter of the vortex according to the free vortex law. Low density buthigh velocity and temperature gas at the center of the vortex isdiffused outwardly and the incoming air is drawn into the vortex, thisprocess maintaining combustion at the center of vortex. The gasesleaving the combustion chamber have a substantially uniform temperaturebecause of mixing and diffusion of hot gases through the incoming air.Only a portion of the air required to produce substantiallystoichiometric ratio is directed into the chamber. The remaining portionis by-passed and is used for cooling the outer walls of the chamber. Thecombustion chamber, because of the vortex path of the gases, furnishes along path of travel to gases entering it, and therefore, it has a higherthermal efliciency than the chambers with shorter paths. Because ofhigher air velocities obtainable with the disclosed chambers, it hashigher specific heat releases (Btu./ft. /hr./atmosphere of pressure)than the combustion chambers known to the prior art.

Referring to Fig. 1, it illustrates a vertical sectional view of a jetpower plant utilizing a two-stage centripetal compressor, a toroidalchamber revolving with the second stage of the compressor and atwo-stage radial flow centrifugal turbine. The compressor includes astationary contra prerotation stage It and first and second supersoniccompression stages 11 and 12. The turbine includes the first stage, orthe input stage, 14, and the second, or output stage 15. Stages 11 and15 are connected through a hollow cylindrical member 16-1 6a having twoparts bolted together by means of bolts 17. Stages 12and 1 are similarlyconnected through a hollow cylindrical member 18, 18a connected in thecenter by means of bolts 19. For a more detailed description of theover-all structure and operation of the power plant, reference is madeto the parent application Serial No. 217,347 now U.S. Patent 2,804,747more fully identifled previously in this application.

The toroidal combustion chamber constitutes an integral part of theinner rotor which includes the second compressor stage 12, cylindricalmember 18l8a input turbine stage 14, the toroidal combustion chamber 20,a centrally-mounted fuel duct 221 an outer, toroidallyshaped outercooling duct 24; and an inner, or centrally located cooling duct 26. Theentire inner rotor assembly is mounted on a shaft having left and rightportions interconnected to each other through the second rotor membersillustrated in Fig. 1, this second rotor revolving in one directionwhile the first rotor, mounted on the second shaft not visible in Figure1, revolves in the opposite direction. Accordingly, the compressor andthe turbine stages are contra-rotatable stages. A,

The toroidal combustion chamber, as viewed in Fig. 1, includes, anouterperipheral member, which may be called the semi-toroid member 2828awhich is joined along the outer periphery at 2 9 in any suitablemanner such as a welded joint. The semi-toroid 2 828a'is held in spacedrelationship with respect to the cylindrical members 1818a by members41, 42, 134, 1 34} (Fig. 3) and bolts 4-3 and 4-4 with the result thata'cooling duct 24 is formed between theouter surface of wall '28- 28aand the inner surface of the cylindrical member bustion chamber.

input turbine duct 215.

Iii-18a. Wall 28-28 a is provided with a plurality of enters duct 24and, after flowing throughthis duct,

leaves it, as illustrated by an arrow 34 whereupon it enters the firststage 14 of the turbine. The input portion of duct 24 may be provided-withan airfoil 35 for assisting efiicient turning of air at this pointin theduct. i

The outer semi-toroid 28-28a is fastened to the inner 37 and 38,-semi-toroid 28 being provided with circularly shaped flanges 39 and 40,whilethe inner toroid is provided with circularly shaped, orring-shaped, seats 41 and 42. The two semi-toroids (the-actual anglesubtended by the outer and inner semi-toroids need not-be and is notequal to 180". Therefore, the term semi is used here only in anapproximate sense and for a lack of a better term; the angle subtendedby the port portion of. the toroid is less than 180) are fastened toeach other by means of a plurality of studs 43 and 44 uniformlydistributed around the periphery of the two joints.

The inner semi-t'oroid includes the centrally, or axially, positionedfuel duct 22 which is connected to a' fuel pump driven by one of theshafts of the power plant,

turbine. 14--15 providing the necessary motive power. .The right end ofthe fuel duct 22 is closed 01f at 46 and the same end of the duct isprovided with 16 radially disposed fuel conduits 132, Figs. 1, 2 and 3,which are .drilled through transverse ribs, or radial vanes, 134, 135,136, 137, 138, etc. Figs. 1, 2 and 3, these radial vanes formingfleightinput ports 140 through 147 and eight output ports 148 through 155.The-outer ends of the radial conduits 13-2 terminate in sixteen fuelnozzles 156 which supply the fuel in gaseous form into the centraltoroid.

The compressed air, after leaving the second compressor stage, followsfour paths; the first path leads to the input ports 1'40147 which conveythe air into the central combustion chamber toroid; the second path, al-

though it by-passes the combustion chamber proper,- it

nevertheless flows through the input ports 140---147 and leaves theseports through slots 200207; it is then mixed with hot gases leaving thechamber through the output ports 14S155; the third path follows theouter duct 24 surrounding the outer periphery of the combustion chamber,and the fourth path follows the'inner duct 26 which is next to the innerperiphery of the combustion chamber, the last two paths cooling thewalls of the com- The first path is indicated in Fig. 1 by arrows 180;the second path is indicated by arrows 181; the third and fourth pathsare indicated by the arrows 34 and 183, respectively. The third path isalso illustrated in Fig. 2 by duct '24, the fourth by duct 26, the firstby the ports 14G147 and the second path by eight output ports 14815'5.Referring to Figs. 2 and. 3, duct 26 is concentric with the fuel duct 22and extendsthrough the entire axial length of the combustion chamber,whereupon it joins the input duct of the turbine, as illustrated in Fig.l.

The first path, i.e., the air used for combustion, enters input ports1481-4 47, which are wedge shaped, with the sharp end of the wedge orthe apex of the triangularly shaped segment, pointing in the directionof the turbine.

The apex of this wedge forms a circularly-shaped path- 185, Fig. :l, todirect the incoming air into the toroid of the chamber. These apices arealso provided with slits, or slots, 2lw-2tl7, Figs. 1, 2 and 3, whichpermit some of the air topass directly from the input ports into theThese slots are provided to insure uniform mixing of hot and cold gases.Because of g the wedge-shaped configuration of the input ports 140--147, and the circular terminations of these ports, by far the largestportion of theair entering these ports enters combustion chamber 20. Hotgases leave combustion chamber 20 through the output ports 148-155,which are also wedge-shaped, with the wide open ends .of the wedgespointing in-the direction of .the. turbine. "Thus, the compressed airiinput ports, supplying air to the com- :bustion. chamber,arefinterleaved, or. interlaced, with the Y hot gas 'output ports, theside-walls of the compressedf fair ports also constitutingithe walls'ofthe hot gas output semi-toroid 36 by rneans of two circularly-shapedjoints eliminates needless losses] From the description of thecombustion heat generator flow losses.

dynamic compression.

' ports, i.e., thetwo types of ports having ,commonwalls,

and being nested adjacent toeach other to form a right cylinder.Examination of the geometryof these ports indicates that the outerportion or periphery, of the toroidal vortex, i.e., adjacent to theinput side of the chamber, will have interleaved streams of relativelycool.

air .(approx. 550 F.) and hot gases, the cool air entering thecombustion chamber and the hot gases leaving it. The same type ofinterleaved, alternating streams of cool air and hot gases will bepresent immediately on the output side of the combustion chamber and'theinput duct of the turbine Where uniform gas stream is obtained not byturbulent mixing but by mutual diffusion between the cool and hotstreams. Elimination of turbulent mixing it follows that: blowing out ofthe flame front is prevented by making the diameter of the toroidsufficiently large to prevent such occurrence even when the air velocityreaches very high value; this is so because of the stationary nature ofthe flame locus; high thermal efiiciency is obtained by providing longair path and efficient diffusion and a moderate degree of mixing of hotgases with cool air; low pressure drop is achieved because of lowaerodynamic resistance of the entire combustion chamber. The combustionchamber, besides achieving the thermodynamic and aerodynamicimprovements, has a number of mechanical advantages, not present in theprior art. Stated briefly,'they are: compound curvature, whichapproaches in its configuration a sphere, produces low stresses in theshell of the toroid, although the total weight of metal is lower, andthe overall dimensions are smaller; the latter produces a chamber havingsmaller axial length, thus shortening the overall length of power plant.I he chamber also has a lowratio of wetted surface to volume, thusreducing friction losses due to flow; however, what is more important interms of the mag nitude of actual aerodynamic losses, thedisclosed-generator eliminates aplarge number of orifices used in theannulus and canister generators which produce principal The combustionheat generator hashigher natural period in transverse direction than thenatural period of the prior art chambers, thus contributing to.

quieter operation of the power plant and longer life of the chamber.There is less likelihood of carbon deposit because of free flow, and,finally, the chamber has a wider utility because of its applicability toall types of In thecharnber shown i'n Fi gs. "1-3, the'fuel duct iscentrally located, along, the axis of the power plant, and

the input and output ports are mounted inconc'ent ric relationship withrespect to the fuel duct. Theport structure defines a cylindrical locuswith the axis of this cylinder coinciding with the axis ofthe' powerplant. The outer portion of the toroid circumferentially surrounds allof the input and output ports. The above configuration, i.e., thecentral location of the input and output ports, with the outer portionof the vortex surrounding them, is the natural concomitant when powerplant uses-a centripetal flow compressor and a centrifugal flow turbine.

The basic principles of the combustion chamber, i.e.,

free vortex and fixed combustion locus, are applicable pr'essors,whether centrifugal or axial.

to any type of dynamic compression known, which includes-thecentrifugal, centripetal and axial compressors. "In the case of 'thecentrifugal and axial compressors,

however, it is "more advantageous to position the entry and the -exit'portsalong the outer periphery of the toroid "sor to the chamber wouldencounter at once the outer periphery rather than the inner periphery ofthe toroid. Figures 4, and "6 illustrate a toroidal combustion chamberof the above type. The combustion chamber, in "this version, is astationary member located between a compressor and a turbine."illustrated in Figs. 4, 5 and 6 originally was disclosed in Thecombustion chamber the co-pending application, Serial No. 216,305, filedMarch 19, 1951, now US. Patent 2,809,493, issued October 15, 1957.Therefore, Figs. 4-6 constitute a divisional application of the aboveparent application.

Referring to Fig. 4, air enters the combustion chamber in a tangentialdirection with respect to the outer periphery of the toroid, asillustrated by arrows 400 and 401, through an annular input duct 402which is also visible in a plan view in Fig. 6. It is to be noted thatFig. 6 represents the View of the chamber taken along a circularlycurved plane 6--6 which plane is then placed -in the single plane of thedrawing for simplifying the drawing.

The combustion chamber consists of an outer toroidal shell 404 and aninner toroidal shell 406. The two toroids are spaced from each other,the space between the two shells being used for circulating compressedair around the outer surface of the inner toroid for cooling wall 406 ofthe inner toroid. The inner toroid 406 constitutes the toroidalcombustion chamber proper where air and fuel are mixed and burned. Theentire combustion chamber is supported by a stationary frame 407 of thepower plant. The two toroids are displaced from the concentric positionwith respect to each other to make duct 420 a constant velocity duct.Fuel is introduced into the input ports of the inner toroid by means. ofa plurality of fuel nozzles 408 which are uniformly distributed aroundthe circular periphery portion 409 of frame 407. One fuel nozzle isprovided for each input port; these fuel nozzles are visible, in a planview,'in Fig. 6. Each input port is also provided with a spark plug 410for igniting the fuel-air mixture upon its formation in the input ports.

The compressed air is introduced into the cooling duct 460 by means of aplurality of input ports 412, which are also visible in Fig. 5, and alsoin Fig. 6. In Fig. 6 only the discharge ends 413 of these ports arevisible in this figure. The compressed air, therefore, enters the inputports 412 in the manner indicated by arrow 401 in Fig. 4, and then flowsthrough the tubularly shaped length of these ports until it emerges fromthese tubular ports'a't 414, Fig. 4. Ports 412 begin at the entry intothe chamber and at exits 414. Upon entering ports 412,

the compressed air flows around the toroid, as illustrated by arrows415, whereupon it enters the discharge ports 416 which are adjacent tothe input ports 412, as illustrated in Fig. 5. Therefore, the compressedair entering the cooling duct 412 describes 360 and travels along thepath of a gradual spiral, the pitch of the spiral being determined bythe angular displacement between the input ports 412 and the outputports 416. Upon leaving the tubularly shaped output ports 416, theheated air enters an annular output duct 418 which leads to a turbine.The turbine may be either an axial flow turbine or a centripetal flowturbine so that duct 418 is a short duct leading directly into thestator vanes of the turbine which impart proper direction of flow of thegases entering the rotor of the turbine. Directing of flow ofthe'compressed air from ducts 412 to ducts 416 is obtainedby'interposing wall member 420 in duct 404 for closing off the inputFigs. 4 to 6 as a stationary chamber.

ports so that the compressed air can leave duct 404 only through theducts 416. I

The central toroid 405 is provided with a plurality o f sector-shaped,or wedge-shaped, m'aininput and output ports 422 and 424 which areplaced around the outer "illustrated as spanning the upper sector of theinner toroid 405. The compressed air enters the main input ports 422 inthe manner illustrated by arrows 430, and

it leaves the input ports in the manner illustrated by arrows 432, theburning gases being directed into the toroid 405 by the circular wall406 of the inner toroid.

The burning gases form a centrally located vortex of burning gases whichis located in the center of the central toroid 405. Hot gases leave thecentral toroid 405 through the output ports 424 in the mannerillustrated by arrows 434.

In the description of the combustion chambers given above, thecombustion chamber in Figs. 1 to 3 was illustrated as being a rotatablechamber and the chamberin It should be apparent that either one chambercan be made either stationary or rotatable. If the chamber illustratedin Figs. 4-6 is made rotatable, then the fuel will have to be introducedfrom the center of the chamber, in the manner illustrated in Figs. 1 to3.

It should also be understood thatthe volume of the main input ports 422(wedge-shaped sectors) maybe made smaller than the volume of the mainoutput ports This can be accomplished by reshaping the walls 426, 427,428 in the manner illustrated in Fig. 6, which increases the volume ofthe output ports as compared to the volume of the input ports. Thisconfiguration or the ports is consistent with the increase in volume ofgases leaving the chamber as compared to the volume of compressed airentering the chamber. The increase in volume is due to a marked rise intemperatureof the gases and generation of additional gases, such ascarbon dioxide and super heated water vapor, when fuel is burned in thecombustion chamber.

In summarizing the discussion relating to the volumes of the main inputand output ports, one general rule which should be kept in mind is thatit is a good practice to keep the entry Mach number equal to the exitMach number. In such a case, the ratio of the exit-to-entry It may beshown that, for constant Mach numbers, M and M at the entry and exit ofthe chamber,

5L L 1 A? T.

where T, and T are the absolute temperatures of gases;

and

C2 T2 -V From (2) and (3), it follows that the area ratio and thevelocity ratio are proportional to the square root of the temperatureratio for constant Mach number.

If this is taken as a condition fordetermining the'entry and the exitareas of the input and output ports, and this is not mandatory, one mayderive, by way of example, for

and much higher Mach number at the exit, and the area ratio A /A couldbe equal to 1.0 without any marked detriment, provided such velocityrelationship is suitable for overall design. The shape of themaininputand output ports, such as ports 422, 424 and ports 148155, hasbeen described in the specification as being wedge-shaped. Suchdescription is only approximately correct because the wedgeshapedconvergence of the ports takes place in a vertical plane toward thecenter, as illustrated in Fig. 2, for example, and there is also awedge-shaped convergence in the direction of the longitudinal axis 170,as illustrated in Fig. 3. Such dual wedge-shaped form will bereferredings in said toroid for discharging heated gases from saidtoroidadjacent the central axis thereof, said input and output portsbeing in communication with substantially circularly curved portions ofthe inner surface of said toroidal combustion chamber whereby airpassing from said input ports into said chamber and heated gases passfrom said chamber to said output ports describe a transverse free vortexof gases revolving substantially about theperipheral circularcenter-line of said toroid.

3. A combustion chamber including-a fuel duct,.a plu rality of input.and output ports mounted inconcentric relationship withrespect to saidfuel duct, said input ports interleaving, or interlacing with, saidoutput ports, a combustion chamber shaped as a hollow toroid, the innerportion of said toroid having a common volume with all of said ports,whereby saidports are positioned within the inner portion of said,toroid, said input ports having a first set of openings in said toroidfor conveying compressed air into said toroid and said output portshaving'a second said toroid, and a second air duct shaped as a hollow toin the claims as the dual wedge-shaped convergence for lack of a betterterm.

What I claim is: i

1. A combustion chamber comprising a hollow toroid having an innersurface; the cross-sections of said toroid taken on planes passingthrough the central axis of said toroid being substantially circular; aplurality of input ports positioned within said toroid; said input portsbeing spaced from one another about and in substantially concentricrelation to the central axis of said toroid, each said input port havingan intake portion positioned to receive compressed air in a directionsubstantially tangent to said toroid and substantially parallel to thecentral axis of said toroid; said input ports terminating at asubstantially circularly curved inner surface within said toroid fordischarging said air along said substantially circularly curved innersurface of said toroid thereby to create a transverse free vortex ofgases within said toroid revolving substantially about the peripheralcircular center-line of said toroid; means for injecting fuel into saidtoroid; and a plurality of output ports positioned within said toroid;said output ports being spaced from one another in interleaved relationto said input ports, each said output port having a gas-receivingportion defined, in part, by the inner substantially circularly curvedsurface of said toroid, and an output portion for discharging said gasesaway from said toroid in a direction substantially tangent to saidtoroid and substantially parallel to the central axis of said toroid. a

2. A combustion chamber including an elongated fuel duct, a plurality ofinput and output ports mounted in a substantially circular arraydisposed in substantially concentric relationship with respect to saidfuel duct, said input ports interleaving, or interlacing with, saidoutput ports, and a combustion chamber shaped as a hollow toroid havingsubstantially circular cross-sections on planes passing through thecentral axis of said toroid, said toroidal combustion chamber beingdisposed in surrounding relationship to said fuel duct whereby said fuelduct is disposed substantially along the central axis of said toroidalchamber with said ports being positioned between said fuel duct and.portions of said combustion chamber adjacent said central fuel duct, theinner portion of said toroid having a common volume with all of saidinput and output ports, whereby said ports are positioned within theinner portion of said toroid, said input ports having a first set ofopenings in said toroid for conveying compressed air into said toroidadjacent the central axis thereof and said output ports having a secondset of opensemi-toroid adjacent to and in spaced relationship withrespect to the outer portion of said toroid, said first and second airducts normally carrying compressed for cooling said toroid. 1

4. A combustion chamber comprising a hollow toroid having a plurality ofinput and output wedge-shaped, or sector-shaped, ports having baseportions and apex portions, said chamber receiving compressed air at thebase portions of said input ports and discharging gases into said toroidat the apex portions of said input ports, said output ports receivinghot gases at the apex portions of said output ports and discharging saidhot gases at the bases of said output ports, said input portsinterleaving, or interlacing, said output ports, and the apices of theinput ports pointing in the opposite direction to the apices of theoutput ports. r p

5. A combustion chamber as defined in claim 4 which also includes afirst set of slot-shaped openings at the apices of the input ports and asecond set of slot-shaped openings at the apices of the output ports,said first set of openings conveying compressed air from said inputports into exhaust gases and said second set of openings conveyingcompressed air intosaid output ports.

6. A combustion chamber as defined in claim 4 in which said input andoutput ports have common sidewalls, and fuel ducts imbedded in saidside-walls, said ducts terminating in fuel nozzles for spraying fuelinto compressed air entering said input ports.

7. A combustion chamber comprising a first, hollow inner toroid and asecond, hollow outer toroid surrounding said first toroid andasymmetrically spaced from said first toroid to form a constantcross-sectional area flow channel between said first and second toroids,a first plurality of input and output ports for said flow channel, saidinput ports interleaving said output ports, said first plurality ofports being positioned between said toroids, and a second plurality ofinput and output ports, said second input ports conveying compressed airinto said first toroid, and said second output ports discharging heatedgases from said first toroid.

8. A stationary combustion chamber for a gas turbine power plantpositioned between a dynamic compressor, supplying compressed air tosaid chamber, and a turbine receiving hot gases from said chamber, saidchamber comprising a first hollow toroid having a plurality of inputports having input and output portions, said input ports havingtriangularly-shaped cross section in a transverse plane of progressivelydecreasing area as one progresses from the input portion to the outputportion of each input port, the output portions of said input portsfollowing the inner circular surface of said toroid, the compressed airfrom said compressor entering said input portions of said input portsand then tangentially discharging into said toroid, a plurality ofsimilarly shaped output ports having similarly shaped input and outputportions, the input ports interleaving, or interlacing, the outputports, the input portions of the input and output ports beingtadjacentto each other along the periphery of said toroid whereby the compressedair and products of combustion create a gaseous vortex within saidtoroid, said products of combustion discharging from said toroid in thesame direction as the compressed air entering said toroid.

9. The combination of claim 1 wherein the entry crosssectional area A ofthe input ports and the exit cross-sectional area A of the output portsfollow the relationship:

where T is the absolute temperature of air entering said toroid, and Tis the absolute temperature of gases leaving said toroid.

12 10. The combination of claim 1 in which the dimensions of the inputand output ports are proportioned to approximate the relationship:

port and M is the Mach number at the exit from an output port.

References Cited in the file of this patent UNITED STATES PATENTSv2,243,467 Jendrassik May 27, 1941 2,360,130 Happner Oct. 10, 19442,665,549 Newcomb- Jan. 12, 1954 FOREIGN PATENTS 942,386 France .i Sept.13, 1948

